In general, the means for guiding a sliding door comprise a rail that is visible on the bodywork outside the motor vehicle, with the sliding door moving along the rail when it is opened or closed.
Such a rail spoils the appearance of the vehicle and does not leave total freedom in design, in particular because the vehicle body which serves to support the rail must extend at least along the full length of the rail. This requires the frame of the sliding door to be positioned at a distance from the end of the vehicle that is not less than the width of the door itself.